Thermoplastic pavement marking materials have become the most widely used durable pavement markings on asphalt pavements such as asphalt roads. Preformed thermoplastic marking materials are much superior to painted marking materials since their service life is as long as the asphalt surface. These marking materials conventionally are colored thermoplastic materials, usually about 0.025 to 0.125 inches thick, normally white or yellow in color, and are used to define traffic control information, such as pedestrian walkways, the stop line for automobiles and signals for right and left turn lanes.
Such preformed marking materials are installed by two basic processes. In the case of an existing roadway or, in some cases, even in connection with a roadway that is being installed, the preformed pavement marking material is applied to the asphalt surface by means of an adhesive. This is referred to as the overlay process.
In the case of new asphalt surfacing, the accepted practice is to apply the preformed pavement marking material as a part of the final surface preparation of the asphalt roadway. The advantage of inlaying the material in this fashion results in a much greater useful life of the preformed pavement marking material and is generally referred to as the inlay process.
For a variety of reasons it is oftentimes necessary to remove preformed pavement marking material which has been applied to the pavement by either the overlay process or the inlay process.
While this invention is particularly applicable to the removal of preformed pavement marking material, and is so described herein, it also can be used for the removal of strip pavement marking material such as centerlines and edgelines.